An ad hoc committee will plan a public workshop that will examine cross-sector work on obesity prevention, treatment, and weight maintenance. The workshop will explore models of cross-sector collaboration, cooperative projects, and alliances that have promise for reducing the prevalence and consequences of obesity. Workshop speakers will present case studies on existing cross-sector initiatives that engage partners from diverse fields. The workshop will provide a space for attendees to discuss lessons learned from and barriers to establishing cross-sector initiatives, as well as potential applications for their communities, organizations, and institutions. The workshop will consider diverse case studies at the community, state, tribal, national, and international levels. The committee will plan and organize the workshop, identify speakers and discussants, and moderate the discussions. A brief, Individually-authored workshop summary, in addition to a full-length workshop summary, of the presentations and discussions at the workshop will be prepared by a designated rapporteur in accordance with institutional guidelines.